Compaction systems and machines incorporating compaction systems are known for compacting surface materials to increase a density or a stiffness of the surface material. Examples of applications where surface compaction is desired include construction sites to avoid further natural settling of the ground, landfill sites where compaction of the landfill waste into a minimum volume is desired, and asphalt roads and parking lots to avoid further settling of the asphalt, and therefore avoid future cracking of the road or parking lot.
The amount of compaction of these materials may be monitored to determine when the material is compressed to a desired density or stiffness. And in the past, various methods for determining an amount of compaction have been employed. For example, direct measurements of material density may be performed at either random or predetermined locations. The measurements may be made by removing core samples of the material for density measurements, or by sand or water displacement devices. Alternatively, the measurements may be made by some means which does not disturb the material, such as by nuclear gauges, electromagnetic measurement devices, and the like.
The above-noted methods for determining the density or stiffness of the material being compacted only provide indications of density at the sample locations chosen for testing. In addition, the above-noted methods require additional time and work by the persons performing the tests, which may increase costs and reduce efficiency of the compaction process. Furthermore, the methods discussed above which disturb portions of the compacted area are not desirable in some situations, for example, when compacting blacktop in a parking lot, as the disturbance of the surface material may adversely affect the finished product.
U.S. Pat. No. 6,973,821 (“the '821 patent”), entitled “Compaction Quality Assurance Based Upon Quantifying Compactor Interaction with Base Material,” describes effective apparatus and methods for on-board determination of compaction quality based upon a sinkage deformation interaction between the compactor and the base material. One strategy described by the '821 patent includes monitoring an energy interaction between the compactor and the base material. The '821 patent further states that propelling power corresponds to the compactive energy delivered by the compactor to the base material, and may be used as a basis for monitoring the above-noted energy interaction.
However, the apparatus and methods described in the '821 patent may benefit from new apparatus and methods to further reduce uncertainty and to promote accuracy of the on-board determination of compaction quality. Accordingly, aspects of the present disclosure address the above-noted opportunities for improvement in the determination of compaction quality and/or other challenges in the art.
It will be appreciated that this background description has been created to aid the reader, and is not a concession that any of the indicated problems were themselves known previously in the art.